As animals attained larger and more complex bodies, exchanges with environment became more complex. Critically discuss the problems of larger bodies and solutions that solved these problems however led to raise complexity. Consider advances of Cnidaria, Porifera, and Platyhelminthes and comprise in your answer:
a. Description of surface-to-volume relationships as applied to animal growth.
b. Adaptations and behaviour which allowed better exchanges of the oxygen and carbon dioxide.
c. Structural modifications which allowed better processing and distribution of the food.
d. The disadvantages and advantages of mesoderm, the necessity of modifications for elimination of nitrogenous waste, and description of protonephridial function
Min Words: 500